Vehicular towing apparatus using air lift

ABSTRACT

A vehicular towing apparatus incorporates an air bag in association with shock absorbers and a tow bar. The air bag may be selectively inflated and deflated, allowing the tow bar to be raised and lowered at will. In addition, the tow bar may be extended or retracted as desired. Several platform attachments enable the towing apparatus to be used alternatively as an automobile tow bar, a support for motorcycles or bicycles, or other items that may be supported upon a platform. The towing apparatus retracts under the vehicle, and may also serve as a vehicle step or standard trailer ball attachment point.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Ser.No. 60/176,907 filed Jan. 20, 2000, the contents which are incorporatedherein by reference in entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention pertains to land vehicles generally, and morespecifically to an apparatus used to interconnect a towing andtransporting vehicle to a transported load. In one embodiment, thetransported load is a second land vehicle, and may include such diversevehicles as automobiles, utility trucks, motorcycles, trailers and othervehicles and non-vehicles. In a more specific embodiment, the inventionpertains to a multi-purpose apparatus which enables an automobile orutility vehicle to conveniently be towed behind a mobile home,recreational vehicle, camper or the like.

2. Description of the Related Art

When a first vehicle is used to tow a second, a variety of schemes havebeen proposed to enable satisfactory towing. In one approach, the secondvehicle is connected to the first through a flaccid connector such as acord, cable, chain or strap. The flaccid connector will be rated towithstand the forces required to accelerate the towed vehicle, and mayalso provide some degree of resilience to reduce these forces and spreadthem over a greater time interval. While this approach may seem to bethe simplest, and certainly requires a minimum of special equipment, theflaccid connector does not maintain spacing between the two vehicles.Consequently, when the towing vehicle decelerates, the towed vehiclemust somehow be controlled to also brake or slow down. Most frequently,a second driver occupies the towed vehicle, and applies brakes asrequired. In the event the second driver briefly loses attention at thesame time that the front vehicle slows down, a serious accident mayresult. In fact, history has demonstrated repeatedly that the seconddriver is unduly endangered.

A second limitation arises from the design of modern automatictransmissions. Most modern vehicles are equipped with automatictransmissions that cannot be operated under external power. In otherwords, if the trailing vehicle has a modern automatic transmission,simply shifting the transmission into neutral is not sufficient. Towingthe vehicle, even in neutral, may seriously damage the transmission.This is particularly true at highway speeds or if long distances are tobe traversed. Consequently, either the transmission must be disconnectedfrom the wheels, or the drive wheels must somehow be lifted from theground. Disconnecting the transmission is not a task which would beattempted by most persons, and there is no equipment provided in theflaccid connector approach for lifting vehicle drive wheels.Consequently, this technique of using a long flaccid connector betweenvehicles is normally reserved for situations where one vehicle must onlybe towed a very short distance, such as from a ditch or hazard back ontothe roadway, or for short, low-speed transit such as might occur over ashort distance on city streets.

In a second approach to towing, a rigid connector is provided betweenthe vehicles. This may take the form of special linkage that attaches toa ball or other point on the front vehicle, and to the frame, bumper orthe like of the trailing vehicle. A ball somewhere within the draftconnection is required, since the two vehicles will not always maintainthe same planar relationship. For example, when passing through a pothole or dip in one side of the road, the leading vehicle will tilt fromhorizontal. However, the second vehicle will not yet be to the dip, andso will still be horizontal. Without the ball or some other articulatingconnection, undue stresses will be placed upon the vehicles and thedraft connection. Balls and mating sockets are preferred for eliminatingthis undesired stress, owing to their relatively simple construction andthe ability for the draft connection to be moved through threedimensions. In other words, through a ball connection the trailingvehicle may move relative to the towing vehicle left and right, up anddown, or roll about a longitudinal axis. Consequently, the number ofcomponents, complexity and resultant cost are greatly reduced by using aball connection.

In spite of the many advantages of balls, which are very commonly usedin trailers and in some vehicle to vehicle draft connections, the riskof damaging a modern vehicle with an automatic transmission by towingstill remains. Several additional approaches have been taken commonly,each which prevent damage to the transmission or drive train of thetowed vehicle. In the first approach, the towed vehicle is simplycarried upon a larger transport, such as a large flat-bed truck orvehicle transport truck. While this approach works for special purposessuch as delivery of new cars or the transport of racing vehicles, itdoes require that the towing and transport vehicle be very large andhave sufficient space for a second vehicle. This limits the use of thetowing and transport vehicle to only a few specialized needs, andrequires a substantial financial investment in the towing vehicle andstorage space when not in use.

In a different approach, the towing vehicle will use a cable or similarflaccid connector to not only engage the towed vehicle, but to lift itoff of the ground. This technique is used universally by nearly allcommercial tow trucks. Unfortunately, while this technique offers greatflexibility in towing very diverse vehicles, a dedicated vehicle with alarge boom and winch system is also required. Once again then, asubstantial financial investment must be made, and special storageprovided for when this special purpose vehicle is not in use.

Another approach incorporates a set of wheels in a small trailer. Thetowed vehicle drive wheels are driven or placed onto a set of supportsbetween the trailer wheels. The trailer is then connected to the towingvehicle through a ball, allowing multiple axis movement or articulationbetween towing and towed vehicles. Unfortunately, there are stillseveral drawbacks which arise. First of all, the trailer again requiresextra equipment, and also storage space when not in use. A seconddrawback stems from the extra width required within the small trailer.It must not only be the width of the towed vehicle, but must also have aset of wheels even wider. This extra width is generally undesirable,and, where the towed vehicle is already approaching the legal limits forwidth, this will lead to an oversize restriction. Further, the set ofwheels on the small trailer require maintenance, over and above themaintenance already required by the separate vehicle wheels.

A third drawback is actually characteristic of all ball and hitchconnections. When a towed vehicle articulates with respect to the towingvehicle, which may be induced for example by unevenness in the roadsurface, there is nothing provided to absorb the changes in directionbetween the towing and towed vehicles. For example, when a towingvehicle travels across a parking lot that slopes downward towards aroadway, both towing vehicle and trailer are in-line and co-axial.However, as the vehicle enters the roadway, the vehicle will change tohorizontal. The trailer still points downward. At this moment, themomentum of the trailer would continue the trailer tongue in a directiondown into the roadway pavement. Therefore, the towing vehicle ball mustnot only pull the trailer, but must also lift the trailer tongue. Thislifting force results in a shift in the balance of the towing vehicle,effectively reducing the weight of the towing vehicle front wheels. Ifthe transition from parking lot to roadway is sufficiently severe, andthe towing vehicle and trailer are close in weight or the towing vehiclehas a longer distance between the rear wheels and the hitch, this canactually lead to dangerous lifting of the towing vehicle front wheels orloss of traction. Furthermore, the additional shifting of the towingvehicle reduces the comfort of the ride by transmitting these forcesfrom the hitch into the vehicle cabin. This also places undue stressupon the vehicles and components, requiring a substantial under-ratingof the components, so that they can withstand these momentary stresses.

In the prior art, there have been several attempts made at overcomingthe limitations of the popular draft connections. U.S. Pat. Nos.2,452,710 to Allen; 2,463,140 to Bihn; 2,966,369 to Paul, Jr.; 3,223,435to Yarbrough; 3,235,286 to Meadowcroft; 3,239,242 to Adams; 3,241,862 toBunting; 3,250,548 to Boyd; 3,284,098 to Worley; 3,311,389 to Barton etal; 3,680,892 to Olthoff et al; 3,961,813 to Thomas; 4,304,419 toRichardson; 4,351,542 to Lovell et al; and 4,512,593 to Ehrhardt areeach exemplary, and incorporated herein by reference for theirteachings. These illustrate a variiety of resilient couplings betweentwo vehicles. Nevertheless, each of these connections only serve as ashock absorber or adjunct to a standard type of hitch, and do not expandor enhance the application of the connection equipment, nor do theyfully address the objectives of the present invention.

What is desired then is an articulating connection which allows manydiverse loads and vehicles to be towed and transported, withoutunnecessarily reducing the safety or comfort of the towing vehicle, andnot requiring additional passengers or operators other than the singledriver of the towing vehicle.

SUMMARY OF THE INVENTION

Exemplary embodiments and manifestations of the present invention solvethe inadequacies of prior towing apparatus by providing an air bag inassociation with shock absorbers and a tow bar, which providesunprecedented cushion and following for towed vehicles. The air bag ismost preferably a high capacity bag which may be selectively inflatedand deflated, thereby allowing the tow connection to be raised andlowered at will. In addition, the tow bar may be extended or retractedas desired. Several platform attachments enable the towing apparatus tobe used alternatively as an automobile tow bar, a support formotorcycles or bicycles, or other items that may be supported upon aplatform. When not in use, the towing apparatus stows under the vehicleout of the way. The towing apparatus may also serve as a vehicle step orstandard trailer ball attachment point.

In a first manifestation, the invention is an articulated vehicle havinga front section with a source of motive power therein, a rear section,and a flexible joint between the front and rear sections. A framework ispivotal about a first axis and extends to the flexible joint. Asuspension assembly provides variable forces between the front sectionand framework, and includes an air bag, and a means for operativelyadjusting pressure within the air bag. The pressure changes cause theframework to pivot about the first axis and thereby raise and lower theflexible joint during use.

In a second manifestation, the invention is an apparatus for supportinga trailing load upon a towing means during transit. A framework attachesto the towing means. A shaft pivots about a transverse axis, and avariable pressure air bag rotates the shaft about the transverse axis,while simultaneously reducing a peak amplitude of acceleration forcesabout the transverse axis generated between towing means and trailingload during travel.

In a third manifestation, the invention is a vehicular towing apparatus.An extensible shaft pivots about an axis and may be extended radiallytherefrom by a variable amount. A motor is provided for extending orretracting the extensible shaft. A gas container varies in sizeresponsive to internal inflation pressure and external forces appliedthereto, and is coupled to the extensible shaft. A source of pressurizedgas is provided in association with a means for controlling a pressurewithin said gas container, so that the pressure control means may beused to selectively apply pressurized gas to the gas container orrelease pressurized gas from the gas container, to thereby pivot theextensible shaft about the axis. A means is also provided for couplingthe extensible shaft to a second vehicle.

OBJECTS OF THE INVENTION

A first object of the present invention is to enable the towing andtransport of diverse loads without requiring vehicles limited solely tothe purpose of towing. A second object of the invention is to enableexisting vehicles to be readily retrofit while maintaining the basicconstruction and configuration of essential components. A third objectof the invention is to provide an apparatus for towing a land vehiclewhich serves to mechanically isolate the towing vehicle from the towedvehicle, thereby improving safety, ride and handling. A further objectof the invention is to enable the towing apparatus to be stored when notin use without requiring separate storage facility or space, and for thetowing apparatus to provide added benefit and utility to the towingvehicle when not in use as a towing apparatus. Yet another object of thepresent invention is for the apparatus to improve the tracking of atowed vehicle and to thereby reduce the skill needed to operate thetowing vehicle and increase the safety of the towing process.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, advantages, and novel features of the present inventioncan be understood and appreciated by reference to the following detaileddescription of the invention, taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 illustrates the primary structural assembly of the preferredembodiment vehicular towing apparatus from a projected plan view, priorto attachment to a towing vehicle.

FIG. 2 illustrates the preferred embodiment vehicular towing apparatusfrom a side plan and schematic view in combination with towing and towedvehicles.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Primary structural assembly 100 of preferred embodiment vehicular towingapparatus 200 includes a towing and transporting platform 110, aframework 130, and a suspension assembly 150. Towing and transportingplatform 110 is provided with small ramps 113 and wheel receiving cusps111 which will serve to support the front wheels 222 of vehicle 220. Ascan be best seen from FIG. 2, a strap 120 maybe provided to securelyattach tire 222 to wheel cusp 111 during transport. In the preferredembodiment, a ratchet 112 is provided to tighten strap 120, as is knownin the general hardware field of tie-down devices. Alternative methodsof attachment between vehicle 220 and platform 110 are contemplated, andwill be obvious to those skilled in the art. For example, while aflaccid strap is most preferred, a chain-type fastener and chain mayalso be used. Furthermore, other vehicles besides passenger cars andutility vehicles may be transported. In such instances, differentgeometries of platforms may be designed and used in accord with thepresent invention to enable the towing and transport of a wider range ofvehicles and things. For example, a motorcycle platform may be providedwhich would enable the motorcycle to be carried entirely upon platform110 in a direction transverse to towing vehicle 210.

Platform 110 may preferably, but optionally, be provided with additionalfeatures including non-slip tread plate 114, which allows a person tostep onto platform 110 safely. A standard ball 118 may additionally beprovided, with the three-hole arrangement if desired, and small stops116 and 117 may be added. A vertical pivot 119 will most preferablyinclude a bushing or bearing which allows rotation about a generallyvertical axis. This allows platform 110 to pivot relative to extensibleshaft 140, as will be further described hereinbelow. Platform 110 mayoptionally be slightly elevated at central region 115 to betteraccommodate the movement of platform 110 with respect to shaft 140.

Extensible shaft 140 connects platform 110 to framework 130. Framework130 is pivotal about an axis parallel to the longitudinal direction ofaxle tube 131. Axle tube 131 terminates in mounting plates 138. Thespecific use of axle tube 131 and mounting plates 138 is not critical tothe invention, other than the provision of a sturdy and pivotal supportfor the remainder of framework 130 and structural assembly 100.Structural tubes 132, 133 form a structural A-frame extending from axletube 131 to suspension tube 135. Between tubes 132, 133 is outer casing134, which is most preferably rigidly attached to both axle tube 131 andsuspension tube 135. Extra structural plates 136, 137 may be providedspecifically for this purpose. While plates 136, 137 are illustratedonly at the junction between casing 134 and suspension tube 135, thoseskilled in the art will recognize that these plates 136, 137 may beomitted entirely, provided other adequate reinforcing or structurallysound methods of attachment are used, or may alternatively be providedat more junctions for structural support, such as between tubes 132, 133and axle tube 131 or suspension tube 135.

At an end of casing 134 distal to platform 110, hydraulic motor 141 willpreferably be mounted and connected to hydraulic lines 142, 143. Motor141 is used to turn a screw or other mechanism traveling inside ofcasing 134, which extends or retracts extensible shaft 140 therein. In asimple manifestation, motor 141 will turn a screw shaft, and shaft 140will be provided with a threaded nut which slides along the screw shaft.However, there are a variety of mechanical couplings which are known andwould serve the function of extending and retracting shaft 140 equallywell. The use of a hydraulic motor 141 is preferred, since hydraulicmotors are self-lubricating, may be designed to provide great torque,and will not normally be damaged if locked or frozen. Additionally, theuse of a screw shaft in association with hydraulic motor will stronglyinhibit or prevent motion of shaft 140 relative to casing 134, unless oruntil motor 141 is activated. This prevents shaft 140 from moving duringtowing. While not illustrated, additional or secondary apparatus may beprovided to further lock shaft 140 into position relative to casing 134,such as various clamps and the like, to provide a secondary safetymechanism. However, secondary clamping is not essential to the operationof the preferred embodiment. In one contemplated alternative embodiment,shaft 140 may be provided at each end with small wedges or flares thatengage with a restricted neck portion at one or both ends of casing 134.The interaction between the wedges and restricted neck portion willallow shaft 140 to be locked at the fully retracted position or fullyextended position, due to the mechanical engagement between wedge andrestricted neck, while also preventing shaft 140 from extending too farin either direction of travel.

Framework 130 is pivotally supported by axle tube 131, and the amount ofrotation of axle tube 131 is controlled by suspension assembly 150.Assembly 150 is most preferably mounted securely at one or more places,such as through anchor bars 151, 152, to the structural framework oftowing vehicle 210, such as into frame beams or the like. In the absenceof strong structural supports, some type of sufficiently strong supportstructure will need to be provided for in towing vehicle 210, in orderfor primary assembly 100 to support large loads upon platform 110.

An air bag 180 having high capacity, the exact amount which will bereadily determined by those of ordinary skill in the field, but whichfor example may be measured in tens or hundreds of thousands of pounds,is provided between a platform surface 161 and a framework formed by thecombination of crossbar 172 and vertical struts 170, 171. This type ofair bag is commonly used in semi-truck tractors and trailers and is usedto form a part of the suspension system therein. In the preferredembodiment, a forty-thousand pound rating has been tested and determinedto be adequate for the preferred application, but, as noted, other loadcapacities are contemplated herein. The exact configuration of air bag180 is not consequential to the invention, and it is noteworthy herethat air bag 180 may not even include air. In the strictest sense, airbag 180 will include a chamber within which a gaseous medium such as airor other highly compressible gas or fluid may be introduced. The chamberwill then be expansible along at least one axis, responsive to theinternal pressure of the chamber and the forces external to air bag 180.

Most preferably, cover 181 of air bag 180 will be attached to or pressedsecurely against crossbar 172. Vertical struts 170, 171 pass throughholes 153, 154 in platform surface 161, and are in turn anchoredsecurely against suspension tube 135. In operation, air bag 180 may beinflated through air line 182 to increase the spacing between platformsurface 161 and crossbar 172, which in turn raises suspension tube 135.This has the overall effect of raising platform 110. FIG. 2 illustratesframework 130 raised to a position approximately horizontal, or parallelto the ground. By releasing air from air bag 180 through air line 182,it is also possible to lower platform 110, most desirably down to groundlevel. The rating of air bag 180 should be great enough not only toaccommodate any load upon platform 110, but also to provide adequatetolerance for momentary increases in load such as may occur when a bumpor obstacle in roadway 250 is encountered.

Air bag 180 is most preferably used in combination with a pair of 90-10shock absorbers 155, 156. Shock absorbers 155, 156 allow platform 110 toraise easily, but resist the lowering thereof. When used in combinationwith air bag 180, a towed or carried load such as platform 110 floatsgently over roadway 250. Air bag 180 provides substantial cushioning,which, in combination with shock absorbers 155, 156, limits transmissionof forces up and down on the back of towing vehicle 210 whilesimultaneously providing a gentler transit for towed cargo such asvehicle 220 or other cargo such as a fully suspended bicycle, motorcycleor cargo box.

In the prior art, particularly when towing vehicle 210 is carrying aheavy load, bumps in roadway 250 tend to alternately lift the frontwheels of towing vehicle 210 off of roadway 250 and force the frontwheels down against roadway 250. This inconsistent force upon the frontwheels is damaging to the tires and potentially hazardous to thehandling and driving of towing vehicle 210. Consequently, in the priorart, towing vehicle 210 had to have sufficient weight in front of therear axle to act as a counterweight against the cargo load being towedor supported upon the hitch behind the rear axle, and the front axle hadto be rated for loads much greater than the vehicle load alone.

This problem of increased and decreased forces upon the front axle oftowing vehicle 210 is an even greater problem where the rear wheels 212of towing vehicle 210 are moved forward from the back bumper, such ascommonly found on many school buses and recreational vehicles, and asillustrated herein in FIG. 2. Torque is measured as a function of forcemultiplied by the distance from the pivot point, so, for a given forceor load down upon the hitch, the torque is greater as the distance fromthe pivot point, which is the rear axle, increases. In these instances,in the prior art the load carrying capacity was much more adverselyimpacted where the hitch is spaced significantly from the rear axle.With the present air bag and shock absorber combination, thisinconsistent loading of the front wheels is virtually eliminated.Furthermore, framework 130 serves to shift the load forwardsubstantially, bringing the hitch force much closer to the rear axle.

A set of rollers 173, 174 assist vertical travel of air bag 180 whilelimiting rotation about an axis transverse to towing vehicle 210, byacting on vertical struts 170, 171. In effect, these help to keep airbag 180 upright while preventing interference between struts 170, 171and platform surface 161. Shock absorber pivots 157-160 are provided forshock absorbers 155, 156. These provide a pivot point and physicalanchor. While illustrated in the drawing as emanating from platformsurface 161, these pivots 157-160 may be anchored separately fromplatform surface 161. The separate anchoring of shock absorbers 155, 156reduces the stresses placed upon platform anchors such as anchor bars151, 152. As aforementioned, a wide variety of anchoring points andattachment methods are contemplated for attaching the suspensionassembly 150 to towing vehicle 210. In many cases, the exact structurewill depend upon the physical construction of the towing vehicle andappropriate locations available for attachment and support.

As illustrated schematically by blocks in FIG. 2, the preferredembodiment towing apparatus 200 includes a hydraulic pump and control230, which is used to activate hydraulic motor 141. In addition, apneumatic pump and control 240 is also provided, which controls thepressure of air within air bag 180. As shown in FIG. 2, air bag 180 isinflated sufficiently to raise towed vehicle 220 from roadway 250. Fortravel along roadway 250, it will normally be desired to raise platform110 sufficiently to provide adequate clearance above roadway 250, whilestill allowing air bag 180 and shock absorbers 155, 156 to support andcushion the load created by towed vehicle 220.

To load vehicle 220 for towing using preferred platform 110, a personwill lower platform 110 to the ground by deflating air bag 180. This isdone using switches, keypad or the like provided at pneumatic pump andcontrol 240. Shock absorbers 155, 156 will offer some resistance to themotion, helping to assist with a gentle lowering of the platform. Oncelowered to the ground, ramps 113 are extended from wheel cusps 111 tothe position illustrated in FIG. 1. In this position, ramps 113 willmore readily permit drive wheels 222 of vehicle 220 to be driven intocusps 111. Next, strap 120 is extended between ramp 113 and ratchet 112,and tightened securely by rotating ratchet 112. The pneumatic pump andcontrol 240 is once again actuated, this time to increase pressurewithin air bag 180, thereby raising drive wheels 222 off of the ground.The preferred distance between towing vehicle 210 and towed vehicle 220may be set or adjusted through hydraulic pump and control 230, extendingextensible shaft 140 a preferred distance. This distance should be greatenough to accommodate a desired degree of articulation between the twovehicles without contact therebetween during cornering and the like.

Two additional elevated stops 116, 117 may optionally be provided, asshown in FIG. 1 and discussed hereinabove. When extensible shaft 140 isretracted, these two stops 116, 117 will serve to lock platform 110against pivoting by contacting the hitch framework 130 at suspension bar135. As will be apparent, platform 110 may be retracted completely outof the way, and in this position still provides a standard hitch ball118 in the usual position, to which a standard trailer may be connected.Since shaft 140 is extensible, platform 110 and ball 118 may bepositioned at any desired distance from the back of towing vehicle 210.Furthermore, platform 110 may be replaced by other attachment devices. Aball receiver or ball, various carrying platforms designed for cargo,including specifically designed platforms that may be limited to asingle piece of cargo or cargo type, and other such supports may be usedin lieu of or in combination with illustrated platform 110. So, forexample, if a bicycle carrier requiring only 18 inches between the loadcenter and the back of vehicle 210 were required, extensible shaft 140can be positioned to accommodate the carrier without adding any furtherthan the 18 inches. For vehicle transport, a greater distance may berequired, and may be varied depending upon the vehicle being towed. Inthe prior art, a ball was provided adjacent the back of the towingvehicle, and then a long arm pivoted about the ball. The trailingvehicle was rigidly attached to the long arm. As a result, whencornering, the trailing vehicle tended to travel inside of the towingvehicle, requiring additional space for cornering. In the presentinvention, the ball or rotational joint is provided at the end of theextensible shaft adjacent the towed vehicle. This forces the towedvehicle to trail much more directly behind the towing vehicle,simplifying cornering.

For front-wheel drive vehicle 220 illustrated in FIG. 2, front wheels222 are elevated and vehicle 220 is ready to be towed. Preferredplatform 110 may, however, be replaced with an inverted ball-receiver ifdesired, and rear-wheel drive vehicles may be directly connected toreceiver hitches already present on the towed vehicle. In this instance,vehicle drive wheels 222 will need held off of the ground using chainsor other restraints. Connection between vehicles 210, 220 is stillgreatly simplified over the prior art, and the performance of thearticulating connection improved by the presence of air bag 180.

To simplify connection between vehicles even further, an electricaltrailer harness may be provided directly from one vehicle to the otherusing standard connectors. For example, a front-wheel drive vehicle 220can be retrofit with a standard trailering electrical connection at thefront side, for example near or just under the front bumper. Towingvehicle 210 may be electrically coupled from a standard electricaltrailer connector directly into the front-wheel drive vehicle 220electrical jack, and additional lights may be unnecessary. This will beparticularly advantageous for those applications such as with arecreational vehicle, where the same vehicle will be regularly towed.

While the foregoing details what is felt to be the preferred embodimentof the invention, no material limitations to the scope of the claimedinvention are intended. Further, features and design alternatives thatwould be obvious to one of ordinary skill in the art are considered tobe incorporated herein. The scope of the invention is set forth andparticularly described in the claims hereinbelow.

What is claimed is:
 1. A retractable towing attachment for convenientlyloading and transporting a motor vehicle behind a recreational vehicleand which is retractable to only expose a standard ball hitch receiver,comprising: an axle tube anchored to said recreational vehicle andextending parallel and adjacent to a rear axle of said recreationalvehicle; a framework longitudinally displaced rearward relative to saidrecreational vehicle from said axle tube and supporting therein anextensible shaft extendible between a retracted position and an extendedposition; a platform attached to said extensible shaft distal to saidaxle tube and supported thereon, said platform supporting said motorvehicle thereon; a suspension assembly platform anchored at a firstposition to said recreational vehicle; a pair of vertical strutsextending between said framework and said suspension assembly; acrossbar extending between said vertical struts; an air bag and at leastone shock absorber each extending between said crossbar and saidsuspension assembly platform; a pneumatic pump and control for inflatingsaid air bag and responsive thereto raising said motor vehicle into atransporting position and for deflating said air bag and responsivethereto lowering said motor vehicle to the ground.
 2. The retractabletowing attachment of claim 1 further comprising rollers between saidplatform and said vertical struts to permit relative vertical motiontherebetween while restraining horizontal motion therebetween.
 3. Theretractable towing attachment of claim 1 further comprising a stopattached to said platform which locks to said framework in saidretracted position.
 4. The retractable towing attachment of claim 3wherein said recreational vehicle vertically extends rearward of saidplatform when said platform is in said retracted position.
 5. Theretractable towing attachment of claim 4 further comprising a ball hitchsupport extending from said platform rearward of said recreationalvehicle when said platform is in said retracted position.